It is known in such devices to provide the EMC filtration by means of common mode filters the capacitors of which are grounded by way of a common ground plane of the printed circuit board of the device, but such an arrangement has been found to create an impedance network linking the capacitors to the detriment of the EMC filtration. It is an object of the present invention to produce a printed circuit device of the kind specified in which the aforementioned disadvantage is minimised.